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Tue, 28 Jul 2015 15:00:24 +0200Tue, 28 Jul 2015 15:00:24 +0200Higher plant proteins of cyanobacterial origin: are they or are they not preferentially targeted to chloroplasts?http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37088
Roman G. Bayer; Tina Köstler; Arpit Jain; Simon Stael; Ingo Ebersberger; Markus Teigearticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37088Tue, 28 Jul 2015 15:00:24 +0200Measurement of charged jet suppression in Pb-Pb collisions at √sNN = 2.76 TeV http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/34389
A measurement of the transverse momentum spectra of jets in Pb-Pb collisions at sNN−−−√=2.76 TeV is reported. Jets are reconstructed from charged particles using the anti-kT jet algorithm with jet resolution parameters R of 0.2 and 0.3 in pseudo-rapidity |η|<0.5. The transverse momentum pT of charged particles is measured down to 0.15 GeV/c which gives access to the low pT fragments of the jet. Jets found in heavy-ion collisions are corrected event-by-event for average background density and on an inclusive basis (via unfolding) for residual background fluctuations and detector effects. A strong suppression of jet production in central events with respect to peripheral events is observed. The suppression is found to be similar to the suppression of charged hadrons, which suggests that substantial energy is radiated at angles larger than the jet resolution parameter R=0.3 considered in the analysis. The fragmentation bias introduced by selecting jets with a high pT leading particle, which rejects jets with a soft fragmentation pattern, has a similar effect on the jet yield for central and peripheral events. The ratio of jet spectra with R=0.2 and R=0.3 is found to be similar in Pb-Pb and simulated PYTHIA pp events, indicating no strong broadening of the radial jet structure in the reconstructed jets with R<0.3.articlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/34389Tue, 28 Jul 2015 14:02:55 +0200Intervention planning using a laser navigation system for ct-guided interventions: a phantom and patient studyhttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37387
OBJECTIVE: To investigate the accuracy, efficiency and radiation dose of a novel laser navigation system (LNS) compared to those of free-handed punctures on computed tomography (CT).
MATERIALS AND METHODS: Sixty punctures were performed using a phantom body to compare accuracy, timely effort, and radiation dose of the conventional free-handed procedure to those of the LNS-guided method. An additional 20 LNS-guided interventions were performed on another phantom to confirm accuracy. Ten patients subsequently underwent LNS-guided punctures.
RESULTS: The phantom 1-LNS group showed a target point accuracy of 4.0 ± 2.7 mm (freehand, 6.3 ± 3.6 mm; p = 0.008), entrance point accuracy of 0.8 ± 0.6 mm (freehand, 6.1 ± 4.7 mm), needle angulation accuracy of 1.3 ± 0.9° (freehand, 3.4 ± 3.1°; p < 0.001), intervention time of 7.03 ± 5.18 minutes (freehand, 8.38 ± 4.09 minutes; p = 0.006), and 4.2 ± 3.6 CT images (freehand, 7.9 ± 5.1; p < 0.001). These results show significant improvement in 60 punctures compared to freehand. The phantom 2-LNS group showed a target point accuracy of 3.6 ± 2.5 mm, entrance point accuracy of 1.4 ± 2.0 mm, needle angulation accuracy of 1.0 ± 1.2°, intervention time of 1.44 ± 0.22 minutes, and 3.4 ± 1.7 CT images. The LNS group achieved target point accuracy of 5.0 ± 1.2 mm, entrance point accuracy of 2.0 ± 1.5 mm, needle angulation accuracy of 1.5 ± 0.3°, intervention time of 12.08 ± 3.07 minutes, and used 5.7 ± 1.6 CT-images for the first experience with patients.
CONCLUSION: Laser navigation system improved accuracy, duration of intervention, and radiation dose of CT-guided interventions.Tatjana Gruber-Rouh; Clara Lee; Jan Bolck; Nagy N.N. Naguib; Boris Schulz; Katrin Eichler; Rene Aschenbach; Julian L. Wichmann; Thomas J. Vogl; Stephan Zangosarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37387Tue, 28 Jul 2015 09:42:49 +0200Cytotoxicity and infiltration of human NK cells in in vivo-like tumor spheroidshttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37386
BACKGROUND: The complex cellular networks within tumors, the cytokine milieu, and tumor immune escape mechanisms affecting infiltration and anti-tumor activity of immune cells are of great interest to understand tumor formation and to decipher novel access points for cancer therapy. However, cellular in vitro assays, which rely on monolayer cultures of mammalian cell lines, neglect the three-dimensional architecture of a tumor, thus limiting their validity for the in vivo situation.
METHODS: Three-dimensional in vivo-like tumor spheroid were established from human cervical carcinoma cell lines as proof of concept to investigate infiltration and cytotoxicity of NK cells in a 96-well plate format, which is applicable for high-throughput screening. Tumor spheroids were monitored for NK cell infiltration and cytotoxicity by flow cytometry. Infiltrated NK cells, could be recovered by magnetic cell separation.
RESULTS: The tumor spheroids were stable over several days with minor alterations in phenotypic appearance. The tumor spheroids expressed high levels of cellular ligands for the natural killer (NK) group 2D receptor (NKG2D), mediating spheroid destruction by primary human NK cells. Interestingly, destruction of a three-dimensional tumor spheroid took much longer when compared to the parental monolayer cultures. Moreover, destruction of tumor spheroids was accompanied by infiltration of a fraction of NK cells, which could be recovered at high purity.
CONCLUSION: Tumor spheroids represent a versatile in vivo-like model system to study cytotoxicity and infiltration of immune cells in high-throughput screening. This system might proof useful for the investigation of the modulatory potential of soluble factors and cells of the tumor microenvironment on immune cell activity as well as profiling of patient-/donor-derived immune cells to personalize cellular immunotherapy.Ariane Giannattasio; Sandra Weil; Stephan Klöß; Nariman Ansari; Ernst H. K. Stelzer; Adelheid Cerwenka; Alexander Steinle; Ulrike Köhl; Joachim Kocharticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37386Tue, 28 Jul 2015 09:20:45 +0200Abscisic acid negatively interferes with basal defence of barley against Magnaporthe oryzaehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/34808
Background: Plant hormones are well known regulators which balance plant responses to abiotic and biotic stresses. We investigated the role of abscisic acid (ABA) in resistance of barley (Hordeum vulgare L.) against the plant pathogenic fungus Magnaporthe oryzae.
Results: Exogenous application of ABA prior to inoculation with M. oryzae led to more disease symptoms on barley leaves. This result contrasted the finding that ABA application enhances resistance of barley against the powdery mildew fungus. Microscopic analysis identified diminished penetration resistance as cause for enhanced susceptibility. Consistently, the barley mutant Az34, impaired in ABA biosynthesis, was less susceptible to infection by M. oryzae and displayed elevated penetration resistance as compared to the isogenic wild type cultivar Steptoe. Chemical complementation of Az34 mutant plants by exogenous application of ABA re-established disease severity to the wild type level. The role of ABA in susceptibility of barley against M. oryzae was corroborated by showing that ABA application led to increased disease severity in all barley cultivars under investigation except for the most susceptible cultivar Pallas. Interestingly, endogenous ABA concentrations did not significantly change after infection of barley with M. oryzae.
Conclusion: Our results revealed that elevated ABA levels led to a higher disease severity on barley leaves to M. oryzae. This supports earlier reports on the role of ABA in enhancing susceptibility of rice to the same pathogen and thereby demonstrates a host plant-independent function of this phytohormone in pathogenicity of monocotyledonous plants against M. oryzae.Sylvia Ulferts; Rhoda Delventhal; Richard Splivallo; Petr Karlovsky; Ulrich Schaffratharticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/34808Tue, 28 Jul 2015 08:32:21 +0200Quantification of LV function and mass by cardiovascular magnetic resonance: multi-center variability and consensus contourshttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/33567
Background: High reproducibility of LV mass and volume measurement from cine cardiovascular magnetic resonance (CMR) has been shown within single centers. However, the extent to which contours may vary from center to center, due to different training protocols, is unknown. We aimed to quantify sources of variation between many centers, and provide a multi-center consensus ground truth dataset for benchmarking automated processing tools and facilitating training for new readers in CMR analysis.
Methods: Seven independent expert readers, representing seven experienced CMR core laboratories, analyzed fifteen cine CMR data sets in accordance with their standard operating protocols and SCMR guidelines. Consensus contours were generated for each image according to a statistical optimization scheme that maximized contour placement agreement between readers.
Results: Reader-consensus agreement was better than inter-reader agreement (end-diastolic volume 14.7 ml vs 15.2–28.4 ml; end-systolic volume 13.2 ml vs 14.0–21.5 ml; LV mass 17.5 g vs 20.2–34.5 g; ejection fraction 4.2 % vs 4.6–7.5 %). Compared with consensus contours, readers were very consistent (small variability across cases within each reader), but bias varied between readers due to differences in contouring protocols at each center. Although larger contour differences were found at the apex and base, the main effect on volume was due to small but consistent differences in the position of the contours in all regions of the LV.
Conclusions: A multi-center consensus dataset was established for the purposes of benchmarking and training. Achieving consensus on contour drawing protocol between centers before analysis, or bias correction after analysis, is required when collating multi-center results.Avan Suinesiaputra; David A. Bluemke; Brett R. Cowan; Matthias G. Friedrich; Christopher M. Kramer; Raymond Kwong; Sven Plein; Jeanette Schulz-Menger; Jos J. M. Westenberg; Alistair A. Young; Eike Nagelarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/33567Tue, 28 Jul 2015 08:14:47 +0200The histone acetylase activator pentadecylidenemalonate 1b rescues proliferation and differentiation in the human cardiac mesenchymal cells of type 2 diabetic patientshttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/33624
This study investigates the diabetes-associated alterations present in cardiac mesenchymal cells (CMSC) obtained from normoglycemic (ND-CMSC) and type 2 diabetic patients (D-CMSC), identifying the histone acetylase (HAT) activator pentadecylidenemalonate 1b (SPV106) as a potential pharmacological intervention to restore cellular function. D-CMSC were characterized by a reduced proliferation rate, diminished phosphorylation at histone H3 serine 10 (H3S10P), decreased differentiation potential, and premature cellular senescence. A global histone code profiling of D-CMSC revealed that acetylation on histone H3 lysine 9 (H3K9Ac) and lysine 14 (H3K14Ac) was decreased, whereas the trimethylation of H3K9Ac and lysine 27 significantly increased. These observations were paralleled by a downregulation of the GCN5-related N-acetyltransferases (GNAT) p300/CBP-associated factor and its isoform 5-α general control of amino acid synthesis (GCN5a), determining a relative decrease in total HAT activity. DNA CpG island hypermethylation was detected at promoters of genes involved in cell growth control and genomic stability. Remarkably, treatment with the GNAT proactivator SPV106 restored normal levels of H3K9Ac and H3K14Ac, reduced DNA CpG hypermethylation, and recovered D-CMSC proliferation and differentiation. These results suggest that epigenetic interventions may reverse alterations in human CMSC obtained from diabetic patients.Matteo Vecellio; Francesco Spallotta; Simona Nanni; Claudia Colussi; Chiara Cencioni; Anja Derlet; Beatrice Bassetti; Manuela Tilenni; Maria Cristina Carena; Antonella Farsetti; Gianluca Sbardella; Sabrina Castellano; Antonello Mai; Fabio Martelli; Giulio Pompilio; Maurizio C. Capogrossi; Alessandra Rossini; Stefanie Dimmeler; Andreas Zeiher; Carlo Gaetanoarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/33624Mon, 27 Jul 2015 17:06:44 +0200Cytokine-Regulated GADD45G Induces Differentiation and Lineage Selection in Hematopoietic Stem Cellshttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/34373
The balance of self-renewal and differentiation in long-term repopulating hematopoietic stem cells (LT-HSC) must be strictly controlled to maintain blood homeostasis and to prevent leukemogenesis. Hematopoietic cytokines can induce differentiation in LT-HSCs; however, the molecular mechanism orchestrating this delicate balance requires further elucidation. We identified the tumor suppressor GADD45G as an instructor of LT-HSC differentiation under the control of differentiation-promoting cytokine receptor signaling. GADD45G immediately induces and accelerates differentiation in LT-HSCs and overrides the self-renewal program by specifically activating MAP3K4-mediated MAPK p38. Conversely, the absence of GADD45G enhances the self-renewal potential of LT-HSCs. Videomicroscopy-based tracking of single LT-HSCs revealed that, once GADD45G is expressed, the development of LT-HSCs into lineage-committed progeny occurred within 36 hr and uncovered a selective lineage choice with a severe reduction in megakaryocytic-erythroid cells. Here, we report an unrecognized role of GADD45G as a central molecular linker of extrinsic cytokine differentiation and lineage choice control in hematopoiesis.Frederic B. Thalheimer; Susanne Wingert; Pangrazio De Giacomo; Nadine Haetscher; Maike Rehage; Boris Brill; Fabian J. Theis; Lothar Hennighausen; Timm Schroeder; Michael A. Riegerarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/34373Mon, 27 Jul 2015 16:43:15 +0200Use of drug-eluting balloon coronary intervention prior to living donor kidney transplantationhttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/32319
Background: Kidney transplantation is the gold standard of therapy in patients with terminal renal insufficiency. Living donor transplantation is a well-established option in this field. Enlarging the donor’s pool implicates the acceptance of an increased rate of comorbidities. Among them, coronary artery disease is a growing problem. An increasing number of patients, undergoing living donation, receive antiplatelet therapies due to coronary disease.
Case presentation: Here we report about the perioperative treatment with a drug-eluting balloon in a patient with major cardiac risk factors who underwent kidney transplantation.
Conclusion: At the current time no recommendation can be given for the routine use of drug-eluting balloons.Tobias Kammerer; Andres Beiras-Fernandez; Markus Rehm; Manfred Stangl; Markus Guba; Christian Kupatt-Jeremias; Florian Weisarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/32319Mon, 27 Jul 2015 16:31:01 +0200Sharpin prevents skin inflammation by inhibiting TNFR1-induced keratinocyte apoptosishttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37797
Linear Ubiquitin chain Assembly Complex (LUBAC) is an E3 ligase complex that generates linear ubiquitin chains and is important for tumour necrosis factor (TNF) signaling activation. Mice lacking Sharpin, a critical subunit of LUBAC, spontaneously develop inflammatory lesions in the skin and other organs. Here we show that TNF receptor 1 (TNFR1)-associated death domain (TRADD)-dependent TNFR1 signaling in epidermal keratinocytes drives skin inflammation in Sharpin-deficient mice. Epidermis-restricted ablation of Fas-associated protein with death domain (FADD) combined with receptor-interacting protein kinase 3 (RIPK3) deficiency fully prevented skin inflammation, while single RIPK3 deficiency only delayed and partly ameliorated lesion development in Sharpin-deficient mice, showing that inflammation is primarily driven by TRADD- and FADD-dependent keratinocyte apoptosis while necroptosis plays a minor role. At the cellular level, Sharpin deficiency sensitized primary murine keratinocytes, human keratinocytes, and mouse embryonic fibroblasts to TNF-induced apoptosis. Depletion of FADD or TRADD in Sharpin-deficient HaCaT cells suppressed TNF-induced apoptosis, indicating the importance of FADD and TRADD in Sharpin-dependent anti-apoptosis signaling in keratinocytes.Kumari Snehlata; Younes Redouane; Jaime Lopez-Mosqueda; Ryoko Shiraishi; Malgorzata Romanowska; Stefan Lutzmayer; Jan Kuiper; Conception Martinez; Ivan Dikic; Manolis Pasparakis; Fumiyo Ikedaarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37797Thu, 23 Jul 2015 13:46:31 +0200Wilhelm Lötschert (1923-1984)http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37861
Ein langjähriges Mitglied unserer Vereinigung, Professor Dr. Wilhelm Lötschert, verstarb am 29. Juni 1984 plötzlich und unerwartet in Frankfurt am Main. Als Professor für Botanik hat er an der Universität Frankfurt die floristisch-soziologische und ökologische Geobotanik begründet und vertreten. Viele Studenten begeisterte er für die Schönheit der Pflanzenwelt, führte seine Schüler aber auch in Naturschutz- und Umweltprobleme ein. Seinen Schülern war er mehr als ein akademischer Lehrer.Theodor Giesarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37861Wed, 15 Jul 2015 17:39:17 +0200A minimal ubiquitous chromatin opening element (UCOE) effectively prevents silencing of juxtaposed heterologous promoters by epigenetic remodeling in multipotent and pluripotent stem cellshttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37385
Epigenetic silencing of transgene expression represents a major obstacle for the efficient genetic modification of multipotent and pluripotent stem cells. We and others have demonstrated that a 1.5 kb methylation-free CpG island from the human HNRPA2B1-CBX3 housekeeping genes (A2UCOE) effectively prevents transgene silencing and variegation in cell lines, multipotent and pluripotent stem cells, and their differentiated progeny. However, the bidirectional promoter activity of this element may disturb expression of neighboring genes. Furthermore, the epigenetic basis underlying the anti-silencing effect of the UCOE on juxtaposed promoters has been only partially explored. In this study we removed the HNRPA2B1 moiety from the A2UCOE and demonstrate efficient anti-silencing properties also for a minimal 0.7 kb element containing merely the CBX3 promoter. This DNA element largely prevents silencing of viral and tissue-specific promoters in multipotent and pluripotent stem cells. The protective activity of CBX3 was associated with reduced promoter CpG-methylation, decreased levels of repressive and increased levels of active histone marks. Moreover, the anti-silencing effect of CBX3 was locally restricted and when linked to tissue-specific promoters did not activate transcription in off target cells. Thus, CBX3 is a highly attractive element for sustained, tissue-specific and copy-number dependent transgene expression in vitro and in vivo.Uta Müller-Kuller; Mania Ackermann; Stephan Kolodziej; Christian Brendel; Jessica Fritsch; Nico Lachmann; Hana Kunkel; Jörn Lausen; Axel Schambach; Thomas Moritz; Manuel Grezarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37385Fri, 19 Jun 2015 14:02:17 +0200Enterovirus infection of human β-cells activates dendritic cells and triggers innate antiviral responses: are enteroviruses convicted now?http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37384
Comment on "Phagocytosis of enterovirus-infected pancreatic beta-cells triggers innate immune responses in human dendritic cells."Urs Christenarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37384Fri, 05 Jun 2015 10:40:54 +0200Quantitative mass spectrometric profiling of cancer-cell proteomes derived from liquid and solid tumorshttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37244
In-depth analyses of cancer cell proteomes are needed to elucidate oncogenic pathomechanisms, as well as to identify potential drug targets and diagnostic biomarkers. However, methods for quantitative proteomic characterization of patient-derived tumors and in particular their cellular subpopulations are largely lacking. Here we describe an experimental set-up that allows quantitative analysis of proteomes of cancer cell subpopulations derived from either liquid or solid tumors. This is achieved by combining cellular enrichment strategies with quantitative Super-SILAC-based mass spectrometry followed by bioinformatic data analysis. To enrich specific cellular subsets, liquid tumors are first immunophenotyped by flow cytometry followed by FACS-sorting; for solid tumors, laser-capture microdissection is used to purify specific cellular subpopulations. In a second step, proteins are extracted from the purified cells and subsequently combined with a tumor-specific, SILAC-labeled spike-in standard that enables protein quantification. The resulting protein mixture is subjected to either gel electrophoresis or Filter Aided Sample Preparation (FASP) followed by tryptic digestion. Finally, tryptic peptides are analyzed using a hybrid quadrupole-orbitrap mass spectrometer, and the data obtained are processed with bioinformatic software suites including MaxQuant. By means of the workflow presented here, up to 8,000 proteins can be identified and quantified in patient-derived samples, and the resulting protein expression profiles can be compared among patients to identify diagnostic proteomic signatures or potential drug targets.Hanibal Bohnenberger; Philipp Ströbel; Sebastian Mohr; Jasmin Corso; Tobias Berg; Henning Urlaub; Christof Lenz; Hubert Serve; Thomas Oellericharticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37244Mon, 01 Jun 2015 10:37:45 +0200Crystal structure of 2-benzamido-N-(2,2-di­eth­oxy­eth­yl)benzamidehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37287
In the title compound, C20H24N2O4, both peptide bonds adopt a trans configuration with respect to the —N—H and —C=O groups. The dihedral angle between the aromatic rings is 53.58 (4)°. The mol­ecular conformation is stabilized by an intra­molecular N—H⋯O hydrogen bond. The crystal packing is characterized by zigzag chains of N—H⋯O hydrogen-bonded mol­ecules running along the b-axis direction.Abdelaaziz Ouahrouch; Moha Taourirte; Hassan B. Lazrek; Joachim W. Engels; Michael Boltearticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37287Fri, 29 May 2015 12:23:59 +0200A revised infrageneric classification and synopsis of the Afro-Eurasian genus Moraea (Iridaceae: Irideae)http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/34374
Molecular phylogenetic studies of Moraea Mill. and the inclusion of Barnardiella Goldblatt, Galaxia Thunb., Gynandriris Parl., Hexaglottis Vent., Homeria Vent. and Roggeveldia Goldblatt in the genus have rendered the existing infrageneric classification, dating from 1976, in need of substantial revision. In particular, subg. Moraea and subg. Vieusseuxia have been shown to be paraphyletic. We propose a new infrageneric classification, based, as far as current data permit, on phylogenetic principles. Monophyletic subgenera and sections are circumscribed based on molecular phylogenies alone or in combination with morphological considerations. We recognize 11 subgenera, 15 sections and three series, arranged as follows in phylogenetic sequence: Plumarieae; Visciramosae (with sect. Multifoliae and sect. Visciramosae); Moraea (with sect. Moraea and sect. Polyphyllae); Galaxia (with ser. Unguiculatae, ser. Eurystigma and ser. Galaxia); Monocephalae; Acaules; Polyanthes (with sect. Serpentinae, sect. Deserticola, sect. Hexaglottis, sect. Gynandriris, sect. Polyanthes and sect. Pseudospicatae); Grandifl orae; Vieusseuxia (with sect. Integres, sect. Vieusseuxia and sect. Villosae); and Homeria (with sect. Stipanthera, sect. Flexuosae, sect. Homeria and sect. Conantherae). Most are moderately to well circumscribed at the morphological level either by floral or vegetative characters, except subg. Moraea, which includes a small number of unspecialized species apparently not linked by any apomorphic features. With over 27 new species described in the past 25 years and another 60 transferred to the genus, Moraea now includes 214 species. We provide a full taxonomic synopsis of the genus.Peter Goldblatt; John C. Manning; Jan Schnitzlerarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/34374Thu, 28 May 2015 13:39:16 +0200Rainwater harvesting for small-holder horticulture in Namibia: design of garden variants and assessment of climate change impacts and adaptationhttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37418
The design of rainwater harvesting based gardens requires considering current climate but also climate change during the lifespan of the facility. The goal of this study is to present an approach for designing garden variants that can be safely supplied with harvested rainwater, taking into account climate change and adaptation measures. In addition, the study presents a methodology to quantify the effects of climate change on rainwater harvesting based gardening. Results of the study may not be accurate due to the assumptions made for climate projections and may need to be further refined. We used a tank flow model and an irrigation water model. Then we established three simple climate scenarios and analyzed the impact of climate change on harvested rain and horticulture production for a semi-arid region in northern Namibia. In the two climate scenarios with decreased precipitation and medium/high temperature increase; adaptation measures are required to avoid substantial decreases in horticulture production. The study found that the most promising adaptation measures to sustain yields and revenues are a more water efficient garden variant and an enlargement of the roof size. The proposed measures can partly or completely compensate the negative impacts of climate change. Laura Woltersdorf; Stefan Liehr; Petra Döllarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37418Mon, 18 May 2015 12:49:22 +0200Structure and regulatory interactions of the cytoplasmic terminal domains of serotonin transporterhttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37357
Uptake of neurotransmitters by sodium-coupled monoamine transporters of the NSS family is required for termination of synaptic transmission. Transport is tightly regulated by protein–protein interactions involving the small cytoplasmic segments at the amino- and carboxy-terminal ends of the transporter. Although structures of homologues provide information about the transmembrane regions of these transporters, the structural arrangement of the terminal domains remains largely unknown. Here, we combined molecular modeling, biochemical, and biophysical approaches in an iterative manner to investigate the structure of the 82-residue N-terminal and 30-residue C-terminal domains of human serotonin transporter (SERT). Several secondary structures were predicted in these domains, and structural models were built using the Rosetta fragment-based methodology. One-dimensional 1H nuclear magnetic resonance and circular dichroism spectroscopy supported the presence of helical elements in the isolated SERT N-terminal domain. Moreover, introducing helix-breaking residues within those elements altered the fluorescence resonance energy transfer signal between terminal cyan fluorescent protein and yellow fluorescent protein tags attached to full-length SERT, consistent with the notion that the fold of the terminal domains is relatively well-defined. Full-length models of SERT that are consistent with these and published experimental data were generated. The resultant models predict confined loci for the terminal domains and predict that they move apart during the transport-related conformational cycle, as predicted by structures of homologues and by the “rocking bundle” hypothesis, which is consistent with spectroscopic measurements. The models also suggest the nature of binding to regulatory interaction partners. This study provides a structural context for functional and regulatory mechanisms involving SERT terminal domains.Cristina Fenollar-Ferrer; Thomas Stockner; Thomas C. Schwarz; Aritra Pal; Jelena Gotovina; Tina Hofmaier; Kumaresan Jayaraman; Suraj Adhikary; Oliver Kudlacek; Ahmad Reza Mehdipour; Sotiria Tavoulari; Gary Rudnick; Satinder K. Singh; Robert Konrat; Harald H. Sitte; Lucy R. Forrestarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37357Wed, 29 Apr 2015 13:26:03 +0200Tricyclic guanidine alkaloids from the marine sponge Acanthella cavernosa that stabilize the tumor suppressor PDCD4http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37243
A cell-based high-throughput screen that assessed the cellular stability of a tumor suppressor protein PDCD4 (Programmed cell death 4) was used to identify a new guanidine-containing marine alkaloid mirabilin K (3), as well as the known compounds mirabilin G (1) and netamine M (2). The structures of these tricyclic guanidine alkaloids were established from extensive spectroscopic analyses. Compounds 1 and 2 inhibited cellular degradation of PDCD4 with EC50 values of 1.8 μg/mL and 2.8 μg/mL, respectively. Mirabilin G (1) and netamine M (2) are the first marine natural products reported to stabilize PDCD4 under tumor promoting conditions.Tanja Grkovic; Johanna S. Blees; Magdalena M. Bayer; Nancy H. Colburn; Cheryl L. Thomas; Curtis J. Henrich; Megan L. Peach; James B. McMahon; Tobias Schmid; Kirk R. Gustafsonarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37243Wed, 29 Apr 2015 13:08:59 +0200Resveratrol post-transcriptionally regulates pro-inflammatory gene expression via regulation of KSRP RNA binding activityhttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37326
Resveratrol shows beneficial effects in inflammation-based diseases like cancer, cardiovascular and chronic inflammatory diseases. Therefore, the molecular mechanisms of the anti-inflammatory resveratrol effects deserve more attention. In human epithelial DLD-1 and monocytic Mono Mac 6 cells resveratrol decreased the expression of iNOS, IL-8 and TNF-α by reducing mRNA stability without inhibition of the promoter activity. Shown by pharmacological and siRNA-mediated inhibition, the observed effects are SIRT1-independent. Target-fishing and drug responsive target stability experiments showed selective binding of resveratrol to the RNA-binding protein KSRP, a central post-transcriptional regulator of pro-inflammatory gene expression. Knockdown of KSRP expression prevented resveratrol-induced mRNA destabilization in human and murine cells. Resveratrol did not change KSRP expression, but immunoprecipitation experiments indicated that resveratrol reduces the p38 MAPK-related inhibitory KSRP threonine phosphorylation, without blocking p38 MAPK activation or activity. Mutation of the p38 MAPK target site in KSRP blocked the resveratrol effect on pro-inflammatory gene expression. In addition, resveratrol incubation enhanced KSRP-exosome interaction, which is important for mRNA degradation. Finally, resveratrol incubation enhanced its intra-cellular binding to the IL-8, iNOS and TNF-α mRNA. Therefore, modulation of KSRP mRNA binding activity and, thereby, enhancement of mRNA degradation seems to be the common denominator of many anti-inflammatory effects of resveratrol.Franziska Bollmann; Julia Art; Jenny Henke; Katharina Schrick; Verena Besche; Matthias Bros; Huige Li; Daniel Siuda; Norbert Handler; Florian Bauer; Thomas Erker; Felix Behnke; Bettina Mönch; Lorena Härdle; Markus Hoffmann; Ching-Yi Chen; Ulrich Förstermann; Verena M. Dirsch; Oliver Werz; Hartmut Kleinert; Andrea Pautzarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37326Wed, 29 Apr 2015 12:54:43 +0200Direct observation of mobility state transitions in RNA trajectories by sensitive single molecule feedback trackinghttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/35830
Observation and tracking of fluorescently labeled molecules and particles in living cells reveals detailed information about intracellular processes on the molecular level. Whereas light microscopic particle observation is usually limited to two-dimensional projections of short trajectory segments, we report here image-based real-time three-dimensional single particle tracking in an active feedback loop with single molecule sensitivity. We tracked particles carrying only 1-3 fluorophores deep inside living tissue with high spatio-temporal resolution. Using this approach, we succeeded to acquire trajectories containing several hundred localizations. We present statistical methods to find significant deviations from random Brownian motion in such trajectories. The analysis allowed us to directly observe transitions in the mobility of ribosomal (r)RNA and Balbiani ring (BR) messenger (m)RNA particles in living Chironomus tentans salivary gland cell nuclei. We found that BR mRNA particles displayed phases of reduced mobility, while rRNA particles showed distinct binding events in and near nucleoli.Jan-Hendrik Spille; Tim P. Kaminski; Katharina Scherer; Jennifer S. Rinne; Alexander Heckel; Ulrich Kubitscheckarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/35830Wed, 29 Apr 2015 12:40:12 +0200Phenotypic variation of 38 European Ambrosia artemisiifolia populations measured in a common garden experimenthttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/36630
The knowledge of phenotypic variation in the European range of the highly allergenic Ambrosia artemisiifolia L. (common ragweed) is not entirely complete, even though it is an invasive species of utmost concern. We hypothesized the prevalence of phenotypic differentiations between common ragweed populations in the introduced range, and we assumed that those differentiations were related to environmental conditions at the points of origin. Using a common garden experiment, we investigated biomass allocation, growth rates, and flowering phenology of 38 European common ragweed populations originating from a major geographical gradient. We observed considerable phenotypic variation in growth parameters and flowering phenology, e.g. mean aboveground biomass varied from 23.3 to 47.3 g between the populations. We were able to relate most measured traits with environmental parameters prevailing at the points of origin. For example, early growth of ruderal populations was highly correlated with temperature and precipitation at the point of origin. Late growth and flowering phenology were highly correlated with latitude, i.e. individuals from northern populations grew smaller and flowered and dispersed their pollen and seeds up to 5 weeks earlier than individuals from southern populations. We also found a longitudinal gradient in flowering phenology which has not yet been described. The existence of such a high variability in the introduced range may facilitate further range expansion. We suggest that the correlation with environmental variables rests upon genetic variation possibly due to adaptations to the respective environment. To clarify if such adaptation results from multiple events of introduction or as evolutionary response after introduction, genetic investigations are needed.Marion Carmen Leiblein-Wild; Oliver Tackenbergarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/36630Wed, 29 Apr 2015 12:31:57 +0200Chemoresistance is associated with increased cytoprotective autophagy and diminished apoptosis in bladder cancer cells treated with the BH3 mimetic (-)-Gossypol (AT-101)http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37373
Background: Acquired resistance to standard chemotherapy causes treatment failure in patients with metastatic bladder cancer. Overexpression of pro-survival Bcl-2 family proteins has been associated with a poor chemotherapeutic response, suggesting that Bcl-2-targeted therapy may be a feasible strategy in patients with these tumors. The small-molecule pan-Bcl-2 inhibitor (−)-gossypol (AT-101) is known to induce apoptotic cell death, but can also induce autophagy through release of the pro-autophagic BH3 only protein Beclin-1 from Bcl-2. The potential therapeutic effects of (−)-gossypol in chemoresistant bladder cancer and the role of autophagy in this context are hitherto unknown.
Methods: Cisplatin (5637rCDDP1000, RT4rCDDP1000) and gemcitabine (5637rGEMCI20, RT4rGEMCI20) chemoresistant sub-lines of the chemo-sensitive bladder cancer cell lines 5637 and RT4 were established for the investigation of acquired resistance mechanisms. Cell lines carrying a stable lentiviral knockdown of the core autophagy regulator ATG5 were created from chemosensitive 5637 and chemoresistant 5637rGEMCI20 and 5637rCDDP1000 cell lines. Cell death and autophagy were quantified by FACS analysis of propidium iodide, Annexin and Lysotracker staining, as well as LC3 translocation.
Results: Here we demonstrate that (−)-gossypol induces an apoptotic type of cell death in 5637 and RT4 cells which is partially inhibited by the pan-caspase inhibitor z-VAD. Cisplatin- and gemcitabine-resistant bladder cancer cells exhibit enhanced basal and drug-induced autophagosome formation and lysosomal activity which is accompanied by an attenuated apoptotic cell death after treatment with both (−)-gossypol and ABT-737, a Bcl-2 inhibitor which spares Mcl-1, in comparison to parental cells. Knockdown of ATG5 and inhibition of autophagy by 3-MA had no discernible effect on apoptotic cell death induced by (−)-gossypol and ABT-737 in parental 5637 cells, but evoked a significant increase in early apoptosis and overall cell death in BH3 mimetic-treated 5637rGEMCI20 and 5637rCDDP1000 cells.
Conclusions: Our findings show for the first time that (−)-gossypol concomitantly triggers apoptosis and a cytoprotective type of autophagy in bladder cancer and support the notion that enhanced autophagy may underlie the chemoresistant phenotype of these tumors. Simultaneous targeting of Bcl-2 proteins and the autophagy pathway may be an efficient new strategy to overcome their “autophagy addiction” and acquired resistance to current therapy.Jens Mani; Stefan Vallo; Stefanie Rakel; Patrick Antonietti; Florian Gessler; Roman Blaheta; Georg Bartsch; Martin Michaelis; Jindrich Cinatl; Axel Haferkamp; Donat Kögelarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37373Wed, 29 Apr 2015 12:28:12 +0200Selenium supplementation in radiotherapy patients: do we need to measure selenium levels in serum or blood regularly prior radiotherapy?http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37182
Considering the review by Puspitasari and colleagues, an additional discussion of the endpoints of the Se supplementation studies described would be helpful. In our view, selenium can safely be given to selenium-deficient cancer patients prior to and during radiotherapy. Therefore, in order to help the radiation oncologist in decision making, we strongly advocate to determine the selenium status prior to and during a potential adjuvant selenium supplementation, e.g. when trying to ease the side-effects of radiation treatment or in the aftercare situation when the selenium status may become insufficient.Ralph Muecke; Oliver Micke; Lutz Schomburg; Klaus Kisters; Jens Buentzel; Jutta Huebner; Jan Krizarticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/37182Wed, 29 Apr 2015 09:52:47 +0200Loss of lysosome-associated membrane protein 3 (LAMP3) enhances cellular vulnerability against proteasomal inhibitionhttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/36629
The family of lysosome-associated membrane proteins (LAMP) includes the ubiquitously expressed LAMP1 and LAMP2, which account for half of the proteins in the lysosomal membrane. Another member of the LAMP family is LAMP3, which is expressed only in certain cell types and differentiation stages. LAMP3 expression is linked with poor prognosis of certain cancers, and the locus where it is encoded was identified as a risk factor for Parkinson's disease (PD). Here, we investigated the role of LAMP3 in the two main cellular degradation pathways, the proteasome and autophagy. LAMP3 mRNA was not detected in mouse models of PD or in the brain of human patients. However, it was strongly induced upon proteasomal inhibition in the neuroblastoma cell line SH-SY5Y. Induction of LAMP3 mRNA following proteasomal inhibition was dependent on UPR transcription factor ATF4 signaling and induced autophagic flux. Prevention of LAMP3 induction enhanced apoptotic cell death. In summary, these data demonstrate that LAMP3 regulation as part of the UPR contributes to protein degradation and cell survival during proteasomal dysfunction. This link between autophagy and the proteasome may be of special importance for the treatment of tumor cells with proteasomal inhibitors.Jorge Antolio Domínguez Bautista; Michael Klinkenberg; Nadine Brehm; Mahalakshmi Subramaniam; Beatrice Kern; Jochen Roeper; Georg Auburger; Marina Jendracharticlehttp://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/36629Wed, 29 Apr 2015 09:40:42 +0200